Power management in an internet protocol (IP) telephone

ABSTRACT

Power management is provided in an Internet protocol (IP) telephone and system to provide energy savings during times that the IP telephone is not in use or use is not expected. A low-power operating mode disables at least a portion of the IP telephone. The low-power operating mode may be initiated by a command received by the IP telephone from the IP telephone controller according to a schedule, which may be modified locally by the user to individualize the user&#39;s schedule. The low-power operating mode may alternatively be activated manually by a user pressing a special key, sequence or combination. The low-power operating mode is canceled upon an indication that a user either is or should be present at the IP telephone.

FIELD OF THE INVENTION

The present invention relates generally to power management and Internetprotocol (IP) telephones, and more particularly, to an IP phone havingpower management sleep modes.

BACKGROUND OF THE INVENTION

Internet protocol (IP) telephones, also referred to asvoice-over-Internet protocol (VOIP) telephones provide an alternative tosubscriber-line services and equipment and to other offerings such ascable telephone and in business and hotel environments, to traditionalmulti-line key or PBX systems. IP telephones are increasing inpopularity, due to the portability of the telephone connection andrelatively low cost compared to other fixed-location services.

For office locations, an IP telephone set resembling a traditionalkey/PBX exchange telephone set is frequently employed as the telephonedevice, or in hotels, IP phones having fully-featured hotel servicesbutton sets are deployed. IP desktop telephones typically include adirect connection such as an Ethernet port, eliminating the need foranother device, such as a personal computer, to interface the IPtelephone to the Internet for a single connection. Relatively low-costcontrollers capable of routing to multiple IP telephones furtherincrease the flexibility and cost-savings available by using IPtelephones in the office and hotel environments. As the popularity of IPtelephones increases, IP desktop telephones can also expect toproliferate in the home environment, as well.

In office and hotel environments in particular, where large numbers ofdevices are typically left unused on weekends and more than ten hoursper day on weekdays, the power consumption of personal computers andmonitors is reduced by having the devices automatically enter a lowpower consumption state. However, typical IP telephones typically do notimplement such a low-power state, as the display on the telephonegenerally needs to remain visible and the network connection must bemaintained in order to receive an event that indicates a call has beenreceived. The power consumed by a network interface is substantial, andthe use of LAN interfaces for the IP telephone interfaces in the latestcommercially-available models, further increases power consumption.

Subscriber-line telephones traditionally needed no low-power mode, aswhen on-hook, all of the telephone electronics is disconnected, with theexception of the ringer. While some telephones having backlitliquid-crystal (LCD) displays employ backlight dimming after some periodof inactivity, telephone devices do not typically operate in a mannersimilar to personal computers and computer monitors.

Therefore, it would be desirable to provide an IP telephone and methodfor power management that conserves energy by placing the IP telephonein a low-power operating mode when full power consumption is notnecessary.

SUMMARY OF THE INVENTION

Power management is provided in an Internet protocol (IP) telephone andsystem to provide energy savings during times that the IP telephone isnot in use or use is not expected. A low-power operating mode disablesat least a portion of the IP telephone. The low-power operating mode iscanceled upon an indication that a user either is or should be presentat the IP telephone.

The present invention is best understood by reference to the followingdetailed description when read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the invention are setforth in the appended claims. The invention itself, however, as well asa preferred mode of use, further objectives, and advantages thereof,will best be understood by reference to the following detaileddescription of an illustrative embodiment when read in conjunction withthe accompanying drawings, wherein like reference numerals indicate likecomponents, and:

FIG. 1 is a block diagram of a telephone system in accordance with anembodiment of the present invention;

FIG. 2 is a pictorial diagram showing arrangement of components of thetelephone system of FIG. 1 within a building;

FIG. 3 is a block diagram depicting details of desktop IP telephones10A-10D of FIG. 1;

FIG. 4 is a flowchart depicting a method of operation of IP telephones10A-10D of FIG. 1 in accordance with an embodiment of the presentinvention; and

FIG. 5 is a user interface display that may be provided on the displayof IP telephones 10A-10D of FIG. 1, in accordance with an embodiment ofthe present invention.

DETAILED DESCRIPTION

The present invention encompasses network protocol telephones andmethods, including IP telephones, along with telephone systems includingnetwork protocol telephones. The network protocol telephones includepower management capability in which a low-power operating mode isinitiated either by a scheduled timer, a command send from a centraltelephone controller, an indication of proximity of a user received fromsome other device, activation of a special key or special keycombination/sequence that places the network protocol telephone in alow-power operating mode, or the like. The telephone exits the low-poweroperating mode in response to user activity, an indication of userproximity received from the other device, according to a scheduledwake-up time, or the like. The above operation, in particular thescheduled operation in which large numbers of telephones in a hotel oroffice may be de-activated when offices or hotel rooms are unoccupied,represents a significant energy (and therefore cost) savings to abusiness. The features may also be used in a home or othernon-controller based environment to provide energy savings, as well.

With reference now to the figures, and in particular with reference toFIG. 1, an IP telephone system in accordance with an embodiment of thepresent invention is shown. The depicted embodiment is not intended tobe limiting, but only exemplary of the type of telephone system to whichthe methods and structures of the present invention may be applied.Multiple desktop IP telephones 10A-10D are coupled to an IP phonecentral controller 12 by individual local-area network (LAN) connections16. The LAN connection 16 may be 10/100, gigabit connection, or thelike. The LAN connection 16 is in turn coupled to a wide-area network(WAN) connection WAN, through which a remote gateway such as avoice-over Internet protocol (VOIP) gateway 18 can be addressed. As willbe explained in further detail below, IP phone central controller 12,and in some embodiments personal computer 14 play a role in activatingand de-activating one or more power-savings modes of desktop IPtelephones 10A-10D. Program instructions are provided to implementsoftware algorithms and are stored within a memory 11 of IP phonecentral controller 12. The program instructions are executed by aprocessor 13, to provide such functions as a scheduler and messagingfunctionality as described in further detail below, by communicatingwith IP telephones 10A-10D via LAN interfaces 15. The LAN interface 15may be 10/100, Gigabit (10/100/1000) LAN interface, or the like.

Referring now to FIG. 2, an arrangement of components within thetelephone system of FIG. 1 are shown in the form of an officearrangement. Personal computer 14 is connected to a monitor 22 and isproximate to desktop IP telephone 10A, e.g., personal computer 14 anddesktop IP telephone 10A are located on the same desk 20 in the sameoffice. Therefore, a “proximity” association can be made between useractivity on personal computer 14 and expectations that the same user mayneed to operate desktop IP telephone 10A. The proximity association mayalternatively be an “ownership” association, e.g., telephone 10A is usedby person A and personal computer 14 is used by person A, even thoughthey are in someone separate locations, or are surrounded by many otherdevices in the same location, such as in a telephone bullpen. The use ofan association such as those described above in power management ofdesktop IP telephone 10A will be described in further detail below.

Referring now to FIG. 3, details of a desktop IP telephone 10, whichimplements IP telephones 10A-10D of FIG. 1 as described above, areshown. Desktop IP telephone 10 is controlled by a processor 30 thatexecutes program code stored in memory 32 to provide various functionsof the desktop IP telephone 10. The depicted example is onlyillustrative and multiple processors can be provided for differentfunctions within desktop IP telephone 10. However, a single processorimplementation has been shown for clarity. A handset 31 is interfacedthrough an audio codec circuit 33 to processor 30 so that audioinformation received from a microphone in the handset can be convertedby audio codec 33 to information that can be communicated over LAN 16 ofFIG. 1 by Ethernet interface 35. Information received from Ethernetinterface 35 is also converted by audio codec 33 to audio signalsprovided to an output transducer (speaker) of handset 31. Processor 30in combination with audio codec 33, implements a protocol such asSession Initiation Protocol (SIP) or other proprietary protocol tosupport a telephone connection between VOIP gateway 18 and desktop IPtelephone 10.

Processor 30 also controls energy management states within desktop IPtelephone 10. This may include such things as disabling a backlightpower supply 36 that provides power to a backlight within display 34 andsending commands to Ethernet interface 35 to place Ethernet interface 35and the connection in a power-down state. The processor 30 may furthercontrol other power down functions including, but not limited to,disabling the display driver circuitry 34A to remove anyinformation/text on the display 34 itself, powering down LED indicators(such as message waiting indicator), powering down audio circuitryincluding a digital signal processor, etc. Desktop IP telephone 10 alsoincludes a keypad 37 for providing standard and special telephone buttonfunctionality. For example, the keypad 37 may have a button for placingthe desktop IP telephone 10 in an energy savings mode. Desktop IPtelephone 10 may also include a USB interface 38 or another suitableinterface through which a connection can be established to anotherdevice such as personal computer 14, in order to receive proximity orabsence indications as mentioned above. Such indications can also beprovided via packets received at Ethernet interface 35 that originateover a network connection of personal computer 14 or from a service withwhich personal computer 14 is interacting, such as an Internet messagingservice.

Desktop IP telephone 10 implements at least one low-power operating modein accordance with an embodiment of the present invention, and in theexemplary embodiment described below, implements a deep sleep mode ofoperation in which Ethernet interface 35, display 34, backlight powersupply 36, audio codec 33, and LED indicators are disabled. Inaccordance with one embodiment, the processor 30 and memory 32 remainedpowered. By keeping power to the memory 32, the desktop IP telephone 10will not have to reboot and download software from the IP phone centralcontroller 12 when coming out of deep sleep mode. Further, by poweringthe processor 30, a real time clock of the desktop IP telephone 10 cancontinue to function. Keypad 37 is scanned to determine if buttons arepressed (including the hook switch activated by handset 31) andprocessor 30 will generally enter periodic idle or sleep modes exceptwhen detecting activity, or when a wakeup timer has elapsed. The statesof any deactivated devices are generally stored and then restored whenthe low-power operating mode is terminated. In a light sleep mode ofoperation, display backlight power supply 36, audio codec 33, andoptionally display 34 along with any associated status LEDs arede-activated, but Ethernet Interface 35 is maintained in an active stateso that desktop IP telephone 10 can be restored to full-power operatingmode in response to an incoming request such as a telephone call, orother interactive function such as text notifications provided todisplay 34 or status changes indicated by an LED, for example when amessage has been left at a hotel lobby.

Referring now to FIG. 4, a method of energy management of desktop IPtelephones 10A-10D in the system of FIG. 1 is shown. The IP telephones10A-10D are initially powered-up (Step 40). Next, the network (LAN)interface of the desktop IP telephones 10A-10D are initialized andconnections are established to the IP phone central controller 12 (Step41). Upon initial power-on and connection to the IP phone centralcontroller 12, any configuration (and/or program code) that is loadedfrom IP phone central controller 12 is downloaded to desktop IPtelephones 10A-10D. If a message is received from the central controller12 via the LAN interface setting sleep/wake times for desktop IPtelephones 10A-10D (decision 42), the sleep/wake times are stored in IPtelephones 10A-10D and the respective timers as implemented by processor30 of FIG. 3 are set (step 43). If a user edits the sleep/wake times(decision 44) at one of desktop IP telephones 10A-10D, the values arechange to customize them for the individual one of desktop IP telephones10A-10D (step 45). In accordance with one embodiment, the user may editthe sleep/wake times (decision 44) at one of desktop IP telephones10A-10D by pressing one or more buttons on the keypad 37 to place aspecified desktop IP telephones 10A-10D in sleep mode.

If a user enters a sleep command (special key or key combo/sequence orthe sleep timer is activated (decision 46)) then the corresponding oneof desktop IP telephones 10A-10D enters deep sleep mode (step 47). Thetelephone remains in deep sleep mode (step 47) until a user activatesthe telephone or the wake time is reached (decision 48), at which timethe above-described sequence is repeated from step 41 so that thenetwork connection is initialized, but a state bit, generally providedby processor 30, differentiates from a pure power up restart, so thatstep 40 is not repeated when exiting the deep sleep mode.

In the illustrative example, light sleep mode (step 50) is activated inresponse to an indication that the user is absent from the telephonelocation, for example by an Internet messenger presence state thatindicates the user is absent (decision 49). A resident application maybe provided on personal computer 14 to poll for the presence informationand send it to an application programming interface (API) of thetelephone. Alternatively USB interface 38 of FIG. 3 might be coupled topersonal computer 14 of FIG. 1 and receive a power management or otherpresence indication that indicates to desktop IP telephone 10A that thelow-power operating mode should be activated or deactivated. The lightsleep mode is maintained until the user activates the telephone or thepresence status changes to “present” (step 51). Unless the powermanagement scheme is disabled (step 52), the process of steps 40-52 isrepeated.

In the event that power is lost to the IP telephone 10A-10D during thedeep or light sleep mode, the IP telephone 10A-10D will power up to fulloperating state when power is restored by repeating the above sequencestarting at step 41.

The above-depicted flow is only one example of a combination of deepsleep and light sleep modes that may be implemented in accordance withthe present invention. The particular communications, actions ortimeouts that cause activation and de-activation of the low-poweroperating modes as depicted above are not limiting and othercombinations are contemplated by the present invention, includingactivation/deactivation of the light sleep mode by manual means. In thecontext of the present invention, it is understood that “low-poweroperating mode” indicates both light and deep sleep modes, and that thetelephone does not need to be “operating”, at least with respect toproviding voice connections or network connections in order to be in an“operating mode”, including the low-power operating mode(s) of thepresent invention.

Referring now to FIG. 5, a user interface that may be provided by atable 60 displayed on display 34 of FIG. 3 and interacted with viakeypad 37 of FIG. 3 is shown. The depicted table 60 shows a set of Waketimes and Sleep times in 24-hour format that can be transmitted from IPphone central controller 12 and customized (via keypad 37) at eachindividual IP telephone by the corresponding user. Such customizationpermits, for example in an office scenario, a worker to set theirdesktop IP telephone to be active during the times they are usuallypresent at work. Alternatively, table 50 might form part of an HTML pageserved by an IP telephone and accessible via personal computer 14,either via the LAN or via USB interface 38 to provide editing of theWake and Sleep times, as well as other features of the telephone.Further, via any of the user interfaces above, it is contemplated thatthe user may customize the low-power operating modes so that theparticular features disabled for each mode may be set by the user. Forexample, in one system or station it might be necessary or desirable todisable only the backlight in deep sleep mode, but leave the displayactive without the backlight. In another application, or at anothertelephone station, might be acceptable to disable both the display andthe backlight in deep sleep mode.

While the Sleep and Wake functions can be commanded by timer values asdescribed above, the Sleep time may be immediate or “now”, as providedby a special command or time value. Such a command is very useful inhotel applications, in which a property management system (PMS) may becoupled to the telephone system. The PMS can provide indications to IPphone central controller 12 or to individual IP telephones 10A-10D thatcertain rooms are occupied/unoccupied and therefore the telephones inunoccupied rooms can be placed in deep sleep mode.

This disclosure provides exemplary embodiments of the present invention.The scope of the present invention is not limited by these exemplaryembodiments. Numerous variations, whether explicitly provided for by thespecification or implied by the specification, such as variations instructure, dimension, type of material and manufacturing process may beimplemented by one of skill in the art in view of this disclosure.

1. A desktop network protocol telephone set, comprising: a networkinterface for connecting the telephone set to a local area network; anaudio interface for providing audio signals to and from a handset of thetelephone set; a processing circuit responsive to communications fromthe network interface; and a control circuit for selecting between afull power operating mode of the telephone set and a low-power operatingmode of the telephone set, wherein in the low-power operating mode, atleast a portion of the telephone set is disabled.
 2. The desktop networkprotocol telephone set of claim 1, wherein the telephone set comprises adisplay having a backlight, wherein the control circuit further selectsbetween a first low-power operating mode and a second low-poweroperating mode, wherein in the first low-power operating mode thenetwork interface is enabled and the backlight is disabled, and whereinin the second low-power operating mode both the network interface andthe backlight are disabled.
 3. The desktop network protocol telephoneset of claim 2, wherein in the second low-power operating mode at leastone of LED indicators, display circuitry, or audio circuitry is furtherdisabled.
 4. The desktop network protocol telephone set of claim 1,wherein a message received from a central network telephone controllervia the network interface indicates a sleep time for setting thelow-power operating mode.
 5. The desktop network protocol telephone setof claim 3, wherein the message further includes a wake time for thetelephone set to exit the low-power operating mode.
 6. The desktopprotocol telephone set of claim 5, wherein the control circuitimplements an interactive editor, whereby at least one of the wake timeor the sleep time can be changed in conformity with user input receivedby the telephone set.
 7. The desktop protocol telephone set of claim 4,wherein the sleep time is an immediate sleep time, wherein the messageis interpreted by the control circuit as a command to enter thelow-power operating mode without delay.
 8. The desktop network protocoltelephone set of claim 1, further comprising at least one button coupledto the control circuit for manual selection of the low-power operatingmode by a user.
 9. The desktop network protocol telephone set of claim1, further comprising a connection to a personal computer, an indicationcommunicated from the personal computer coupled to the telephone setindicating the low-power operating mode.
 10. A method of operation of adesktop network protocol telephone set coupled to a local area networkby a network interface, comprising: first receiving first networktransmissions from the local area network corresponding to receivedaudio signals; first converting the first network transmissions to afirst audio signal provided to a handset of the telephone set; secondreceiving a second audio signal from the handset; second converting thesecond audio signal to second network transmissions and providing themto the network interface; third receiving an indication that a user ofthe telephone set is not expected to be or is not in proximity to thetelephone set; and selecting between a full power operating mode of thetelephone set and a low-power operating mode of the telephone set inresponse to the indication received by the third receiving, wherein inthe low-power operating mode, at least a portion of the telephone set isdisabled.
 11. The method of claim 10, wherein the telephone set includesa display having a backlight, wherein the selecting further selectsbetween a first low-power operating mode as the low-power operating modeand a second low-power operating mode, wherein in the first low-poweroperating mode the network interface is enabled and the backlight isdisabled, and wherein in the second low-power operating mode both thenetwork interface and the backlight are disabled.
 12. The method ofclaim 11, wherein in the second low-power operating mode at least one ofLED indicators, display circuitry, or audio circuitry is furtherdisabled.
 13. The method of claim 10, wherein the third receivingreceives a message from a central network telephone controller via thenetwork interface, that indicates a sleep time at which the user isexpected to be away from the telephone set and that the low-poweroperating mode can be selected.
 14. The method of claim 13, wherein themessage further includes a wake time for the telephone set to exit thelow-power operating mode, and wherein the method further comprises:determining when the wake time has been reached; and exiting thelow-power operating mode in response to the determining that the waketime has been reached.
 15. The method of claim 14, further comprising:providing an interactive editor using a display of the telephone set;receiving user input for changing at least one of the wake time or thesleep time; and modifying the at least one of the wake time or the sleeptime in conformity with the user input.
 16. The method of claim 13,wherein the sleep time is an immediate sleep time, and wherein themethod further comprises interpreting the message as a command to enterthe low-power operating mode without delay.
 17. The method of claim 10,wherein the third receiving receives a user input selecting thelow-power operating mode, and wherein the selecting is performed inresponse to receiving the user input.
 18. The method of claim 10,wherein the third receiving receives a communication from a personalcomputer coupled to the telephone set and located proximate thetelephone set, wherein the communication provides the indication thatthe user of the telephone set is not expected to be or is not inproximity to the telephone set.
 19. A network protocol telephone system,comprising: a central controller for controlling the telephone system; aplurality of desktop network protocol telephone sets coupled to thecentral controller via network interfaces of the telephone sets, andwherein the central controller sends commands to the telephone sets toplace the telephone sets in a low-power operating mode according to aschedule of times that the telephone sets are expected to not be in use.20. The network protocol telephone system of claim 19, wherein thelow-power operating mode disables a network interface of the telephonesets, wherein the central controller further communicates a wake-up timeto the telephone sets, and wherein the telephone sets include aninternal timer that determines when the wake-up time has been reachedand command the telephone sets to exit the low-power operating mode.